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Trajectoires et relations sociales : le quartier comme ressource et contrainte
No full textWhat does the place of residence change in the trajectory of a person who grows up or lives there, in terms of access to employment, career path? Access to employment is based on the social relations available to family and friends or on the intervention of professionals from training or support organisations, particularly at the start of a career or when a career changes direction (Chauvac 2013).Career choices are also linked to family and friends, with family and friends providing resources to find information, make contacts or receive encouragement, but also models or counter-models, influences, support or constraints (Bidart 2008). The place of residence conditions the wider environment, and can therefore have an impact on an individual's trajectory.Research conducted on the trajectories of people who grew up and/or still live in a urban area qualified as a priority in the sense of urban policy shows that they denounce an effect of assignment to low-skilled or precarious jobs, the mourning of major jobs (Zunigo 2008) and a phenomenon of discrimination. They consider that "the urban area" is a strong explanatory factor of the difficulties and obstacles encountered, more than a resource, even if this may also be the case. Analyzing pathways by taking into account social relations enables us to understand how this "urban area" effect is constructed, but also how the accumulation of social and economic difficulties that characterize the situation of the inhabitants of a priority urban area will multiply the obstacles and crises in individual pathways (Beaud 2018). Around sixty trajectories have been reconstructed using the method of quantified narratives (Grossetti 2011) and the analysis of the modes of access to employment or other resources such as training and permits, in terms of relational chains. The analysis of these trajectories highlights the importance of family social networks in the pathways, often articulated with other modes of access such as the use of devices - in longer chains than previously observed (Chauvac 2011, 2013) - as well as the complexity of certain pathways and their consequences on the lives of the respondents.The social relationships mentioned and/or mobilised by the respondents, the devices at the different stages of their career, depending on their professional situations, also show the sequence of situations. Finally, the interviews make it possible to list the social relationships mentioned and/or used by the respondents, and to characterise them partly according to their professional situations.In the end, analysis in terms of social networks sheds light on the specificities of these pathways, with the urban area functioning above all as a revealer of the impact of social conditions on all biographical transitions.Cet article se fonde sur une recherche participative avec des jeunes habitant·e·s d’un quartier populaire de juin 2018 à juillet 2019 auprès de personnes ayant grandi ou vivant dans leur quartier et travaillant, pour comprendre leurs cheminements professionnels. Une partie des personnes interrogées ont expliqué avoir eu l’impression d’être assignées à des emplois précaires et peu valorisants, avoir dû faire preuve de plus de persévérance pour ne pas être réduites à ce futur que leurs proches, mais aussi les institutions jugeaient probable. L’analyse en termes de chaînes relationnelles, en particulier avec la méthode des narrations quantifiées, permet de comprendre comment se construisent les situations de précarité et d’exclusion et le rôle des dispositifs et des proches pour en sortir
On the primitive subspace of Lando framed graph bialgebra
No full textLando framed graph bialgebra is generated by framed graphs modulo 4-termrelations. We provide an explicit set of generators of its primitive subspaceand a description of the set of relations between the generators. We alsodefine an operation of leaf addition that endows the primitive subspace ofLando algebra with a structure of a module over the ring of polynomials in onevariable and construct a 4-invariant that satisfies a simple identity withrespect to the vertex-multiplication.Comment: 12 pages. Published versio
: a Family of Extensional Type Theories with Effectful Realizers of Continuity
No full text is a generic family of effectful,extensional type theories with a forcing interpretation parameterized bymodalities. This paper identifies a subclass of \text{TT}^{\Box}_{{\mathcalC}} theories that internally realizes continuity principles through statefulcomputations, such as reference cells. The principle of continuity is a seminalproperty that holds for a number of intuitionistic theories such as System T.Roughly speaking, it states that functions on real numbers only needapproximations of these numbers to compute. Generally, continuity principleshave been justified using semantical arguments, but it is known that themodulus of continuity of functions can be computed using effectful computationssuch as exceptions or reference cells. In this paper, the modulus of continuityof the functionals on the Baire space is directly computed using the statefulcomputations enabled internally in the theory
Branch-Well-Structured Transition Systems and Extensions
No full textWe propose a relaxation to the definition of well-structured transitionsystems (\WSTS) while retaining the decidability of boundedness andnon-termination. In this class, the well-quasi-ordered (wqo) condition isrelaxed such that it is applicable only between states that are reachable onefrom another. Furthermore, the monotony condition is relaxed in the same way.While this retains the decidability of non-termination and boundedness, itappears that the coverability problem is undecidable. To this end, we define anew notion of monotony, called cover-monotony, which is strictly more generalthan the usual monotony and still allows us to decide a restricted form of thecoverability problem
OCR quality and the resilience of algorithmic identification of linguistic register features in Eighteenth Century Collections Online
No full textA compositional account of motifs, mechanisms, and dynamics in biochemical regulatory networks
No full textRegulatory networks depict promoting or inhibiting interactions betweenmolecules in a biochemical system. We introduce a category-theoretic formalismfor regulatory networks, using signed graphs to model the networks and signedfunctors to describe occurrences of one network in another, especiallyoccurrences of network motifs. With this foundation, we establish functorialmappings between regulatory networks and other mathematical models inbiochemistry. We construct a functor from reaction networks, modeled as Petrinets with signed links, to regulatory networks, enabling us to precisely definewhen a reaction network could be a physical mechanism underlying a regulatorynetwork. Turning to quantitative models, we associate a regulatory network witha Lotka-Volterra system of differential equations, defining a functor from thecategory of signed graphs to a category of parameterized dynamical systems. Weextend this result from closed to open systems, demonstrating thatLotka-Volterra dynamics respects not only inclusions and collapsings ofregulatory networks, but also the process of building up complex regulatorynetworks by gluing together simpler pieces. Formally, we use the theory ofstructured cospans to produce a lax double functor from the double category ofopen signed graphs to that of open parameterized dynamical systems. Throughoutthe paper, we ground the categorical formalism in examples inspired by systemsbiology.Comment: Final version published in Compositionalit
The Pebble-Relation Comonad in Finite Model Theory
No full textThe pebbling comonad, introduced by Abramsky, Dawar and Wang, provides acategorical interpretation for the k-pebble games from finite model theory. ThecoKleisli category of the pebbling comonad specifies equivalences underdifferent fragments and extensions of infinitary k-variable logic. Moreover,the coalgebras over this pebbling comonad characterise treewidth and correspondto tree decompositions. In this paper we introduce the pebble-relation comonad,which characterises pathwidth and whose coalgebras correspond to pathdecompositions. We further show that the existence of a coKleisli morphism inthis comonad is equivalent to truth preservation in the restricted conjunctionfragment of k-variable infinitary logic. We do this using Dalmau'spebble-relation game and an equivalent all-in-one pebble game. We then providea similar treatment to the corresponding coKleisli isomorphisms via a bijectiveversion of the all-in-one pebble game. Finally, we show as a consequence a newLov\'asz-type theorem relating pathwidth to the restricted conjunction fragmentof k-variable infinitary logic with counting quantifiers.Comment: Extended version of the paper in Logic in Computer Science (LICS) 2022 Proceeding
Local properties and augmented Lagrangians in fully nonconvex composite optimization
No full textA broad class of optimization problems can be cast in composite form, thatis, considering the minimization of the composition of a lower semicontinuousfunction with a differentiable mapping. This paper investigates the versatiletemplate of composite optimization without any convexity assumptions. First-and second-order optimality conditions are discussed. We highlight thedifficulties that stem from the lack of convexity when dealing with necessaryconditions in a Lagrangian framework and when considering error bounds.Building upon these characterizations, a local convergence analysis isdelineated for a recently developed augmented Lagrangian method, deriving ratesof convergence in the fully nonconvex setting.Comment: 36 page
Exploring Non-Regular Extensions of Propositional Dynamic Logic with Description-Logics Features
No full textWe investigate the impact of non-regular path expressions on the decidabilityof satisfiability checking and querying in description logics extending ALC.Our primary objects of interest are ALCreg and ALCvpl, the extensions of withpath expressions employing, respectively, regular and visibly-pushdownlanguages. The first one, ALCreg, is a notational variant of the well-knownPropositional Dynamic Logic of Fischer and Ladner. The second one, ALCvpl, wasintroduced and investigated by Loding and Serre in 2007. The logic ALCvplgeneralises many known decidable non-regular extensions of ALCreg. We provide a series of undecidability results. First, we show thatdecidability of the concept satisfiability problem for ALCvpl is lost uponadding the seemingly innocent Self operator. Second, we establishundecidability for the concept satisfiability problem for ALCvpl extended withnominals. Interestingly, our undecidability proof relies only on one singlenon-regular (visibly-pushdown) language, namely on r#s# := { r^n s^n | n in N }for fixed role names r and s. Finally, in contrast to the classical databasesetting, we establish undecidability of query entailment for queries involvingnon-regular atoms from r#s#, already in the case of ALC-TBoxes
Input Regularization for Integer Optimal Control in BV with Applications to Control of Poroelastic and Poroviscoelastic Systems
No full textWe revisit a class of integer optimal control problems for which atrust-region method has been proposed and analyzed in arXiv:2106.13453v3[math.OC]. While the algorithm proposed in arXiv:2106.13453v3 [math.OC]successfully solves the class of optimization problems under consideration, itsconvergence analysis requires restrictive regularity assumptions. There aremany examples of integer optimal control problems involving partialdifferential equations where these regularity assumptions are not satisfied. Inthis article we provide a way to bypass the restrictive regularity assumptionsby introducing an additional partial regularization of the control inputs bymeans of mollification and proving a -convergence-type result when thesupport parameter of the mollification is driven to zero. We highlight theapplicability of this theory in the case of fluid flows through deformableporous media equations that arise in biomechanics. We show that the regularityassumptions are violated in the case of poro-visco-elastic systems, and thusone needs to use the regularization of the control input introduced in thisarticle. Associated numerical results show that while the homotopy can help tofind better objective values and points of lower instationarity, the practicalperformance of the algorithm without the input regularization may be on parwith the homotopy